diff --git a/refpolicy/doc/policy.dtd b/refpolicy/doc/policy.dtd
index 60b9f48..88e6f94 100644
--- a/refpolicy/doc/policy.dtd
+++ b/refpolicy/doc/policy.dtd
@@ -8,7 +8,7 @@
       name CDATA #REQUIRED
       dftval CDATA #REQUIRED>
 <!ELEMENT summary (#PCDATA)>
-<!ELEMENT interface (description,securitydesc*,parameter+,infoflow)>
+<!ELEMENT interface (description,securitydesc*,parameter+,infoflow?)>
 <!ATTLIST interface name CDATA #REQUIRED>
 <!ELEMENT description (#PCDATA)>
 <!ELEMENT securitydesc (#PCDATA)>